BACKGROUND: Hypertension, a noteworthy hazard for stroke and coronary illness, is one of the most significant preventable causes of premature morbidity and mortality in developed and developing nations. Adherence to antihypertensive medications and lifestyle alterations can greatly affect the control of hypertension. This study investigated factors that impact on treatment compliance of patients on antihypertensive therapy at the National Guard-Health Affairs (NGHA) Primary Health-Care Clinics (PHCC), Dammam, Saudi Arabia, taking into account the Health Belief Model (HBM).MATERIALS AND METHODS: A cross-sectional study was conducted in the NGHA PHCC, Dammam. A total of 402 individuals were included in the study through convenience sampling method. Data were gathered by structured self-administered questionnaire. Data were entered into the computer and analyzed using SPSS software. The data were summarized using frequencies and percentages. The Chi-square test was used to compare ratios, and a Pearson's correlation analysis of HBM variables was carried out; all tests were performed at 0.05 significance level.RESULTS: The proportion of treatment-compliant participants in this study was 39.6%, and the participants' 'mean age was 54.09 (SD±10.703) years. About 59% females were compliant to the treatment regimen as against 19.7% of males. A total of 33.5% of the married participants were compliant, as against 16.7% of the single participants who were compliant. Unemployed patients (72.3%) were more compliant than the employed participants.CONCLUSIONS AND RECOMMENDATIONS: The study showed that the compliance of most hypertensive patients with antihypertensive therapy was poor. Based on the HBM, all predictors including perceived severity, perceived susceptibility, perceived benefits, perceived barriers, and cues to action were statistically significant (P < 0.05). Therefore, the provision of health education by health-care providers to patients could have a substantial positive impact on patient compliance.

Hypertension is a known risk factor for cerebrovascular disease, cardiac disease, chronic kidney disease, peripheral vascular disease, cognitive impairment, and premature death. If left untreated, hypertension can cause a progressive increase in blood pressure (BP), often resulting in a treatment-resistant condition due to vascular and renal damage.[1]

According to the newly released guidelines published by the American Heart Association, the American College of Cardiology, and nine other societies, the hypertension threshold has been lowered from systolic BP 140 mmHg/diastolic BP 90 mmHg to systolic BP 130 mmHg/diastolic BP 80 mmHg, resulting in a new diagnosis in approximately 14% more Americans.[2]

Kearney et al.'s 2005 paper, “Global burden of hypertension: analysis of worldwide data” projected a 60% increase in the number of adults with hypertension to a total of 1.56 billion by 2025.[3] A population-based study in Saudi Arabia reported a prevalence of prehypertension as 66.1%, 48.1%, and 54.9% in males, females, and all participants, respectively, whereas the prevalence of hypertension was 6.0%, 4.2%, and 4.9% in males, females, and all participants, respectively.[4]

Nonadherence to medication is of growing concern and is associated with adverse outcomes.[5] Few studies have been published in Saudi Arabia on the compliance of hypertensive patients. A study in Tabuk, Saudi Arabia, which focused on drug compliance of hypertensive patients concluded that the compliance rate was 53.0%.[6] Another study on the compliance and knowledge of hypertensive patients attending Primary Health-Care clinic (PHCC) centers in AL-Khobar, Saudi Arabia, found the overall compliance rate to be 34.2%.[7]

Long-term noncompliance to therapy severely jeopardizes the efficacy of treatment and adversely affects the condition of the patient.[8]

Materials and Methods

A cross-sectional quantitative design was used to carry out this study over a period of 10 months from January 2018 to October 2018. At the National Guard-Health Affairs (NGHA) PHCC, Dammam, Saudi Arabia, The number of hypertensive patients attending the PHCC is approximately 1810/year. The population of the study consisted of hypertensive patients on antihypertensive treatment and who attended PHCC in Dammam. Assuming the population proportion as 0.5, confidence level as 95%, and a margin of error of 0.05, the required sample size was calculated as 402.[9],[10]

The participants for the study were selected using a convenience sampling procedure because it is quick, is inexpensive, and is convenient.[11] Detection of hypertensive patients took place in the triage room while vital signs were being taken. The nurse selected known hypertensive patients and sent them to the principal investigator and/or the co-investigators to be interviewed and complete the questionnaire. Before the completion of the questionnaire, the participant was asked if he/she had ever been interviewed to avoid any duplication. Using formal questionnaires, the data were collected. The questions, structured according to the Health Belief Model (HBM)-based research goals, highlighted patients' sociodemographic characteristics; perception of severity; their views on sensitivity, benefits, barriers; and cues to action.

The validity of the questionnaire was examined by the team's internist for clarity and specificity of variables. A pretest or pilot test was conducted on 10% of the sample who were then excluded from the real sample of the study. This test was to discover any unclear questions that needed rewording or deletion. Reliability coefficient was, however, not calculated.

Included in the study were patients aged 18 years or more who had received antihypertensive treatment for at least 1 month. Excluded were those <18 years of age and those who were unable to respond to interviews (e.g., patients who were very sick).

The outcome variable was compliance with treatment, which consists of compliance with the drug regimen and lifestyle changes. The evaluation of medication regimen compliance was included in the questionnaire comprising seven items. The HBM variables evaluating the perception of hypertension severity, perception of susceptibility to complications of hypertension, perception of barriers and benefits, and cues to action were also in the questionnaire.

Data were entered into the computer and analyzed using Microsoft Excel version 10, and then transferred to SPSS software. The data were summarized using frequency tables to determine the findings of the data, including frequencies and percentages. Cross tabulations were conducted between variables and demographic characteristics. The Chi-square test was used to compare ratios, and a Pearson's correlation analysis of HBM variables was carried out. P ≤ 0.05 was considered statistically significant.

Compliance with antihypertensive drugs was the dependent variable. Independent variables included sociodemographic characteristics and HBM variables including perceived severity of hypertension, susceptibility to complications of hypertension, benefits of compliance to treatment, barriers to compliance, and cues to action for treatment compliance.

Permission was obtained from the Institutional Review Board of King Abdullah International Medical Research Center to conduct the study. Strict ethical standards and procedures were followed. Participation in the study was entirely voluntary, and permission was obtained from the patients to participate in the study. Informed consent was obtained in writing before interviewing patients. All information obtained was kept strictly confidential, and participants were assured about anonymity. Prior to giving consent, information about the principal investigator was given to the participants, and the purpose of the research was explained to them.[12]

Results

Participating in the study were a total of 402 patients comprising 198 males (49%) and 204 females (51%) aged 18 to 70+ years, with 54.09 (±10.7) years of mean age (±standard deviation [SD]). Their sociodemographic features are shown in [Table 1]. Of the participants, 16% had no formal education, 24% had primary school education, 32% had secondary school education, and 27% had graduated from college. Nearly 79% of the participants were married, and 18% were widowed. Half of the participants had no employment, while the other 50% were employed, of which most (26%) were government employees, 15% were nongovernmental employees, and 9% were businesspeople.

[Table 2] shows the compliance with antihypertensive medications in relation to gender; 58.8% of the females were compliant, while 41.2% were noncompliant. With respect to males, 19.7% were compliant and 80.3% were noncompliant, clearly showing that females were more compliant than males. The relation between participant's age and compliance with medication regimen is also shown in [Table 2]. The proportion of participants who complied with treatment was 159 (39.6%); 32 (20%) of them were in the age group of 56–60 years and had better compliance with antihypertensives than those in the other age groups. While the proportion of participants who did not comply to treatment was 243 (60.4%), 57 (23.5%) of them were aged 46–50 and they were least compliant to antihypertensive treatment with P = 0.002. Compliance with antihypertensive medications in relation to HBM variables is also exhibited in [Table 3] with P < 0.05.

Compliance with the treatment showed a significant positive relation with perceived susceptibility (r = 0.125; P = 0.05), indicating that the higher the perceived susceptibility to complications with hypertension, the better the compliance. Compliance to treatment showed a positive relation with perceived benefit (r = 0.108; P = 0.05), indicating that the higher the perceived benefit of the use of medication, the better the compliance. Compliance with treatment showed a positive relation with perceived treatment barriers (r = 0.134; P = 0.01), indicating that the higher the perceived treatment barriers, the higher the compliance. Compliance with treatment also showed a positive relation with cues to action (r = 0.149; P = 0.01), indicating that the higher the cues to action, the higher the compliance.

Perceived severity showed a positive relation with perceived susceptibility (r = 0.257; P = 0.01), indicating that the higher the perceived severity of the disease, the greater the perception of vulnerability to complications. The perceived severity showed a positive relation with the perceived benefit (r = 0.149; P = 0.01), indicating that the higher the perceived severity, the greater the perceived benefit of taking medication.

Perceived susceptibility showed a positive relation with the perceived benefit of using drugs (r = 0.317; P = 0.01), indicating that the higher the perceived susceptibility of having complications of hypertension, the higher the perceived benefit of using medication. Perceived susceptibility showed a positive relation with perceived treatment barriers (r = 0.183; P = 0.01), indicating that the higher the perceived susceptibility to complications of hypertension, the higher the perceived treatment barriers.

Perceived barriers showed a positive relation with cues to action (r = 0,110; P = 0.05), indicating that the higher the perceived barriers to treatment, the higher following the cues to action (reminders).

Discussion

This study evaluated and explored factors affecting treatment compliance to antihypertensive therapy by hypertensive patients attending the NGHA PHCC, Dammam. This was a quantitative cross-sectional study, and the data were gathered using questions developed in accordance with research goals in formal questionnaires. Compliance to medication regimen was 39.6%, which was less than the results obtained at Tabuk, Saudi Arabia, by Khalil et al. in May 1997, in which the compliance rate was found to be 53.0%.[13]

The study showed that participants aged 56–60 years were better at complying to treatment (20.1%) than those >60 years of age and <56 years of age. These results are comparable to those reported in the February 2018 study by Dedefo and Berisa in Ethiopia, which showed that adherence was more likely to occur among those >55 years of age.[14]

The findings of this study showed that 58.8% of females were compliant, whereas only 19.7% of males were compliant, clearly showing that females were more compliant to treatment than males. This is comparable to the study carried out in September 2017 by Tibebu et al. which concluded that females were better at adhering to instructions on medication than males.[15]

This study also assessed the relationship between HBM variables and treatment compliance and showed a significant positive association with all HBM variables. Consequently, it is highly recommended that counseling and health education should be regularly given to hypertensive patients whenever they attend clinics for routine follow-up.

Nonadherence to medication is of growing concern and is associated with adverse outcomes. Maintaining medication adherence to multiple medications is a complex issue in patients with chronic diseases, particularly cardiovascular diseases. The most important cause of uncontrolled BP is the impact of nonadherence to antihypertensive medications. As a result, most (nearly three quarters) of the hypertensive patients do not achieve optimal control of BP.[16]

This study was conducted in the NGHA PHCC, Dammam; therefore, the results cannot be generalized to all patients with hypertension. However, the results provided important information on what patients believe about hypertension and its complications, which may resemble other NGHA facilities.

The convenience sampling method used to select the study participants is highly vulnerable to selection bias and influences beyond the control of the researcher, as well as high levels of sampling error and low credibility.[17] However, this method was employed because it is fast, simple, readily available, and cost-effective.[18] Furthermore, because of the large number of hypertensive patients attending the clinics, a simple random sampling procedure is difficult to implement.

Conclusions and Recommendations

In this study, compliance rate with antihypertensive treatment was 39.6%. The mean age (±SD) of the study participants was 54.09 (±10.703) years. Compliance with medication schemes, lifestyle changes, perceived severity, perceived susceptibility, perceived benefits, and perceived barriers was statistically significant (P < 0.05) based on Pearson's correlation and Chi-square test.

Based on the results of this study, it is recommended that regular counseling and health education be given to hypertensive patients whenever they attend routine follow-up clinics.

Financial suppot and sponsorship

This study has been sponsored by King Abdullah International Medical Research Center (KAIMRC).

Berisa H, Dedefo M. Non-adherence related factors to antihypertensive medications among hypertensive patients on follow up at Nedjo General Hospital in West Ethiopia. Open Public Health J 2018;11:62-71.